Increased levels of neopterin are found during impaired renal function and viral infection in transplant patients. Elevated levels are also indicators for conditions related to impaired cellular immunity.
Neopterin, a pyrazolopyridine compound, is produced by macrophages after induction by interferon γ and serves as a marker of cellular immune system activation. Measurable levels of neopterin have been detected in both the serum and urine of patients suffering from various types of malignancies1 and viral infections. Changes in neopterin concentrations in serum or urine can predict complications such as graft rejection in organ transplant recipients. Elevated neopterin levels are found in autoimmune disorders such as rheumatoid arthritis and systemic lupus erythematosus (SLE). Neopterin levels can be used as prognostic predictors for certain types of malignancies. Measurement of neopterin levels has particular value for monitoring patients infected with HIV. Neopterin is eliminated primarily in the urine, so evaluation of urinary neopterin levels may be useful in assessing activation of the cellular immunity system even in the absence of typical clinical symptoms, since a correlation has been observed with the course of diseases involving cellular immunity activation and urinary neopterin levels
Serum or plasma
0.3 mL (Note: This volume does not allow for repeat testing.)
Red-top tube, gel-barrier tube, or lavender-top (EDTA) tube
If tube other than a gel-barrier tube is used, transfer separated serum or plasma to a plastic transport tube.
Refrigerate. Protect from exposure to ultraviolet light and sunlight.